A method of this kind is, for example, known from the draft of IETF (Internet Engineering Task Force) “SIP for Telephones (SIP-T): Context and Architectures”. According to this draft, the original signaling message should be accepted in an encapsulated form, a sit is called, in the partner signaling message. This should enable a transparent forwarding of the signaling data, i.e. forwarding without changing the original data structure of the original signaling message, or forwarding that a possible without knowing the significance of the individual data fields of the original signaling message.
According to SIP-T, section 3.2.3, “proxy”, a signaling unit that receives the partner signaling message and cannot process the encapsulated signaling data of the interconnected data transmission network should ignore this signaling data.
The object of the invention is to enable the transmission of signaling data using a simple method, that particularly precludes the misuse of signaling data. Furthermore, corresponding devices, a corresponding signaling message and a corresponding program should be provided.